--- /dev/null
+/*! \file ccspi.c
+ \author Travis Goodspeed
+ \brief Chipcon SPI Register Interface
+*/
+
+//Higher level left to client application.
+
+#include "platform.h"
+#include "command.h"
+
+#include <signal.h>
+#include <io.h>
+#include <iomacros.h>
+
+#include "ccspi.h"
+#include "spi.h"
+
+
+#define RADIOACTIVE SETCE
+#define RADIOPASSIVE CLRCE
+
+//! Set up the pins for CCSPI mode.
+void ccspisetup(){
+ SETSS;
+ P5DIR&=~MISO;
+ P5DIR|=MOSI+SCK;
+ DIRSS;
+ DIRCE;
+
+ //Begin a new transaction.
+ CLRSS;
+ SETSS;
+}
+
+//! Read and write an CCSPI byte.
+u8 ccspitrans8(u8 byte){
+ register unsigned int bit;
+ //This function came from the CCSPI Wikipedia article.
+ //Minor alterations.
+
+ for (bit = 0; bit < 8; bit++) {
+ /* write MOSI on trailing edge of previous clock */
+ if (byte & 0x80)
+ SETMOSI;
+ else
+ CLRMOSI;
+ byte <<= 1;
+
+ SETCLK;
+
+ /* read MISO on trailing edge */
+ byte |= READMISO;
+ CLRCLK;
+ }
+
+ return byte;
+}
+
+
+//! Writes a register
+u8 ccspi_regwrite(u8 reg, const u8 *buf, int len){
+ CLRSS;
+
+ reg=ccspitrans8(reg);
+ while(len--)
+ ccspitrans8(*buf++);
+
+ SETSS;
+ return reg;//status
+}
+//! Reads a register
+u8 ccspi_regread(u8 reg, u8 *buf, int len){
+ CLRSS;
+
+ reg=ccspitrans8(reg);
+ while(len--)
+ *buf++=ccspitrans8(0);
+
+ SETSS;
+ return reg;//status
+}
+
+//! Handles a Chipcon SPI command.
+void ccspihandle(unsigned char app,
+ unsigned char verb,
+ unsigned long len){
+ unsigned long i;
+
+ //Drop CE to passify radio.
+ RADIOPASSIVE;
+ //Raise !SS to end transaction, just in case we forgot.
+ SETSS;
+ ccspisetup();
+
+ switch(verb){
+ //PEEK and POKE might come later.
+ case READ:
+ case WRITE:
+ CLRSS; //Drop !SS to begin transaction.
+ for(i=0;i<len;i++)
+ cmddata[i]=ccspitrans8(cmddata[i]);
+ SETSS; //Raise !SS to end transaction.
+ txdata(app,verb,len);
+ break;
+
+ case PEEK://Grab CCSPI Register
+ CLRSS; //Drop !SS to begin transaction.
+ ccspitrans8(CCSPI_R_REGISTER | cmddata[0]); //000A AAAA
+ for(i=1;i<len;i++)
+ cmddata[i]=ccspitrans8(cmddata[i]);
+ SETSS; //Raise !SS to end transaction.
+ txdata(app,verb,len);
+ break;
+
+ case POKE://Poke CCSPI Register
+ CLRSS; //Drop !SS to begin transaction.
+ ccspitrans8(CCSPI_W_REGISTER | cmddata[0]); //001A AAAA
+ for(i=1;i<len;i++)
+ cmddata[i]=ccspitrans8(cmddata[i]);
+ SETSS; //Raise !SS to end transaction.
+ txdata(app,verb,len);
+ break;
+ case SETUP:
+ ccspisetup();
+ txdata(app,verb,0);
+ break;
+ case CCSPI_RX:
+ RADIOPASSIVE;
+ //Get the packet.
+ CLRSS;
+ ccspitrans8(CCSPI_R_RX_PAYLOAD);
+ for(i=0;i<32;i++)
+ cmddata[i]=ccspitrans8(0xde);
+ SETSS;
+ //no break
+ txdata(app,verb,32);
+ break;
+ case CCSPI_RX_FLUSH:
+ //Flush the buffer.
+ CLRSS;
+ ccspitrans8(CCSPI_FLUSH_RX);
+ SETSS;
+
+ //Return the packet.
+ txdata(app,verb,32);
+ break;
+ case CCSPI_TX:
+ case CCSPI_TX_FLUSH:
+ default:
+ debugstr("Not yet supported.");
+ txdata(app,verb,0);
+ break;
+ }
+
+
+ SETSS;//End session
+ RADIOACTIVE;
+}